Method and apparatus for de-icing submaring snorkels



June 1964 1...! VAN HEUSEN 3,139,054

METHOD AND APPARATUS FOR DE-ICING SUBMARINE SNORKELS Filed Oct. 19, 1960 Fig. I

2 *I MAIN ENG 2 MAIN ENG. 29 COOLER DISC, COOLER DISC.

2a 32 POWER SUPPLY ENGINE ROOM AIR DUCT INVENTOR. LEW/.5 J. VAN HEUSE/V ATTORNEYS head valve.

United States Patent 0 3,139,054 METHOD AND APPARATUS FOR DEE-ICING SUBMARINE SNORKELS Lewis J. Van Heusen, 3844 Kidd Drive, Honolulu 13, Hawaii Filed Oct. 19, 1960, Ser. No. 63,702 3 Claims. (Q1. 11416) (Granted under Title 35, US. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates to a method and apparatus for de-icing submarine Snorkels and, more particularly, to such which involve subjecting the air stream entering the snorkel to a warm water spray.

A snorkel broadly is an air induction conduit whose purpose is to enable intake of air into a submerged submarine. Principal elements of structure thereof are generally defined as the snorkel mast which constitutes the main conduit member and a head valve mounted in the upper or air intake end of this mast. This head valve controls the intake of air into the snorkel and is open when the submarine is snorkeling and is closed when the snorkel head or air-intake end, as it may be called, is below water.

Icing is a continual problem to proper snorkeling operation, especially during prolonged snorkeling in cold water. During snorkeling the induced air is joined by ocean spray, mist, rain, snow, sleet, fog, and the like, to cause troublesome ice formation in the snorkel air induction system. For example, the head valve may become frozen in position to prevent its proper operation or, barring freezing of the head valve, ice can be formed inside the snorkel mast to choke oif proper air induction therethrough. Introduction of any form of fresh water (e.g. mist, rain, fog, snow, etc.) poses a more serious icing difficulty than does the introduction of salt water into the air induction system. This is because fresh water ice is considerably greater in strength than salt water ice.

Previous attempts to solve the icing problem met in snorkeling operations have hinged principally upon the positioning of electrically-heated elements at the mast head in the area of the head valve. These have proven to be generally unsatisfactory. One limitation which these electrically-heated elements have is that their positioning possibilities are necessarily restricted so that they will not mechanically interfere with the operation of the But perhaps the cardinal limitation is that they do not produce enough Btu. output to heat up sufliciently the large volume of fluid which passes through the snorkel during the snorkeling operation. Air moving through the snorkel induction travels at a high rate of speed which increases as the submarine approaches top cruising speed. It is the resultant large fast-moving volume of cold air which drops the temperature of any water companion, such as sea spray, for example, to below its freezing point to cause the troublesome ice formation. Moving ocean salt water starts freezing into ice crystals at 28 F. and is 33% ice crystal at 22 F. Air temperatures in far northern or Arctic waters often reach well below 0 F. It readily can be seen that a large B.t.u. output is necessary to warm up the fast-moving large volume of cold air to a temperature which will preclude the formation of solid ice on protrusions (such as the head valve and the mast internal surface) in the air stream. To provide a safety factor zone for proper snorkeling the temperature to which the induced air mass with its moisture content must be raised will necessarily be higher than the 22 F. mentioned above. The aforementioned electrically-heated elements do not have sufficient thermal capacity to heat the large induced fluid mass to a safe temperature to ensure ice-free snorkeling operation in rigorous climatic conditions.

The present invention comprises a method and apparatus for destroying the eifective ice-forming capability of the unwanted moisture which is an unavoidable companion to the air induced through the snorkel. It taps the main heat source available in the submarine, the heat generated by the main engine(s). Normally this heat is carried off by the main engine cooling system to be discharged overboard as warmed-up salt water. This invention provides for pick-up of this heated brine at the discharge of the main engine coolers and pumping of this hot brine to a plurality of nozzles for spraying the brine into the air mass as the induced air makes its initial entry into the snorkel toward the passage-controlling head valve. The effective heating of the incoming air mass-which is the result which must be achieved to preclude effective ice formation-is predicated not only upon the heat available from this main engine cooling system brines elevated temperature, but also upon the latent heat of fusion present in the sprayed brine; this 980 B.t.u.s per pound, which the sprayed water will generate before it will shift from liquid state to solid state (ice), creates a considerable thermal source, over and above that available from the brine due to its elevated temperature, which the invention applies as a thermal barrier to ice formation. The nozzles are so directed and the heated brine forced therefrom at such pressure as will create over the head valve a hot brine umbrella" through which the induced air must pass. This etfectuates a thermal transference to the incoming air mass which is vastly more effective than that available with the previously-used electrically-heated warming elements. The use of the heated brine from the main engine cooling system discharge provides still another contributing factor to the prevention of the troublesome ice formation. As previously mentioned, salt water ice is considerably less in strength than fresh water ice. Accordingly, the brine spraying, described above, not only heats up the induced fluid mass but, as well, shifts the character of any fresh water moisture induced along with the air to salt water with the result that any ice which possibly might be formed would be a no strength mush.

Some of the other advantages arising from the present,

invention as compared with prior de-icing methods and apparatus are: (1) elimination of grounded circuits, (2) use by the invention of very little power, (3) low cost, (4) the apparatus is easily repairable at sea, and (5) the invention apparatus does not comprise delicate parts (which are frequent trouble sources).

An object of the present invention is the provision of a method and apparatus for de-icing submarine Snorkels.

Other objects and many of the attendant advantages of this invention readily will be appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing where:

FIG. 1 is a schematic-like showing of the apparatus of the invention; and

FIG. 2 is a plan view of an illustrative spray ring and its nozzles.

Referring now to the drawing wherein like reference numerals designate corresponding parts in the several figures, FIG. 1 shows, in schematic-like respresentation, the apparatus of the invention. At the head of snorkel induction mast 11 is located snorkel head valve 12 which opens to admit air when the snorkel head is above water and closes to keep out water when the snorkel head is below water. Head valve 12 is a conventional snorkel head valve which is shown here more-or-less schematically having a valve seat and a valve head which is vertically moved in reciprocating fashion by valve rod to mate with seat 15 when valve 12 is closed and to separate from seat 15 when valve 12 is open to admit air. Mounted to the upper end of snorkel mast 11 in a protective position surrounding head valve 12 is a shield 13. Mounted along the upper portion of this shield 13 is a tubular spray ring 14 having a plurality of circumferentially spaced spray nozzles 16 which are substantially located along the periphery of the air-intake end of shield 13. Shield 13 in etfeot comprises both a protective covering for head valve 12 and a conduit extension of snorkel mast 11. Spray nozzles 16, as best seen in FIG. 2, are in conduit communication with the inner portion of the supporting spray ring 14 and are directed inwardly so that spray issuing from these nozzles will form over head valve 12 a complete spray umbrella through which the air taken into the snorkel must pass. These nozzles are of sufiicient number, of parasol or other suitable type, and are kept at suflicient water pressure to ensure that the umbrella spray created thereby completely envelops head valve 12. The water pressure to the spray nozzles 16 can be increased as necessary to preclude the development of any hole in this spray umbrella, which occurrence might result in ice formation.

The balance of the apparatus consists principally of a conduit system with suitable boosting pumps and control valves for picking up the heated brine from the main engines cooler discharge and carrying it to the spray nozzles 16 at a selectively-controllable pressure. As seen in FIG. 1 the brine from main engine #1 and main engine #2 cooler discharges is piped through alternative routes from each of the engines via the respective stop valves 17 and 18 to a common line which passes through strainer 19 and stop valve 21. The piping routing continues from valve 21 to pump 22 which, driven by pump motor 23 which in turn is controlled by pump motor controller 24, boosts the pressure of the brine from the low pressure available at the cooler discharge to a pressure suitable for generating the required pressure at the spray nozzles 16. By-pass valve 26 enables pump 22 to be by-passed when necessary. The piping routing continues from pump 22 to control valve 27 and thence through consecutive brine overload stop and sea valves 28 and 29, respectively. Leaving stop and sea valve 29 the piping passes through the submarine hull to form an externally-mounted section which leads to the snorkel induction mast 11. This externally-mounted section of piping is protected by rubber lagging 30. Following control valve 27 is a pressure gauge 31 which is inserted in the piping to measure the pressure in the line and intermediate this pressure gauge 31 and the brine overboard stop and sea valve 28 is an air intake line which admits air to the main line (brine line), when desired, from a low pressure air supply 32 by means of air-admission control-valve 33. Upon reaching the snorkel induction mast 11 the solid piping passes through bulkhead fitting 34 into the mast to immediately join, by means of adapter 36, a flexible hose 37. This flexible hose 37, of suflicient length to accommodate to the raising and lowering of the snorkel, continues the brine conduit system to the head portion of the snorkel mast 11 where it connects once again, by way of adapter 38, to a solid piping which passes through bulkhead fitting 39 and runs along the outside of mast 11 and then inside shield 13 to connect into spray ring 14 at 41.

By means of the just-described conduit system the heated water from the engine cooling system is boosted by pump 22 to deliver it at the predetermined required vol ume and pressure to the spray nozzles 16 for maintaining a complete holeless spray umbrella over the head valve 12 at all air intake speeds. Pressure gauge 31, which manifests the pump 22 discharge pressure, enables operator surveillance over the brine pressure to indicate required pressure changes for maintaining the desired pressure at the spray nozzles 16.

Positioned near control valve 27 is a distant reading thermometer 42 whose temperature sensor 43 is located in the engine room air duct. By varying the degree of opening of control valve 27, located in the line at the dis charge side of pump 22, the amount of salt water sprayed from nozzles 16 into the induced air stream can be varied. With the operational minimum brine pressure maintained at the nozzles 16, the temperature of the induced air, as registered by distant-reading thermometer 42, is dependent upon the amount of salt Water sprayed from nozzles 16 as controlled by control valve 27. With a minimum of 12 psi. pressure maintained at the spray nozzles 26 F. has been settled upon as the temperature to be maintained in the engine room air duct to prevent ice formation in the snorkel induction system. By keeping surveillance over distant reading thermometer 42 an operator can vary control valve 27 to maintain this temperature in the fluid in the engine room air duct. Unnecessarily pushing this temperature beyond this level by increasing the amount of warm salt Water delivered to spray nozzles 16 has the ill effect of putting more water than necessary into the induction system with a resultant unnecessary filling of the negative tank which receives for disposal the water taken intothe air induction system. Thermometer 44, located alongside the temperature sensor 43 of distant reading thermometer 42, is available as a check on the accuracy of the readings on the distant-reading thermometer 42 and for calibration purposes therefor.

Low pressure air supply 32 is available for blowing the brine out of the system when desired.

As related hereinbefore in detail the method and apparatus herein utilize both the temperature available from the main engine cooling system and the latent heat of fusion available from the brine sprayed into the induced air and, in addition, the advantage derived from converting any fresh water intake into salt water intakewhich tends to produce a much weaker ice formation than its fresh Water cousin.

Obviously many modifications and variations of the present invention are possible in the light of the above teaching by the exercise of routine skill in the art and it is intended that all such variations be embraced by the appended claims.

What is claimed is:

1. A method for preventing icing of a submarine snorkel having an air intake control valve in the head portion thereof which comprises picking up heated water from any source of heated water aboard said submarine, conveying said heated water to the area of said air intake control valve and forming by nozzle discharge of said heated water at the weather side of said air intake control valve an umbrella-like spray configuration which completely envelops the weather-side of said air intake control valve.

2. A method for preventing icing of a submarine snorkel having a valve mounted in its head portion 1 for. controlling the admission of fluid whose principal component is air into the snorkel which comprises the steps of picking up hot brine from the submarine engine cooling system, pumping said hot brine to said snorkel head valve area and discharging said hot brine above said head valve in the form of spray having an umbrella-like configuration which completely envelops the weather-side of said head valve.

3. The combination, in a submarine, of:

(a) a snorkel comprising:

(1) a main fluid-passing conduit member adapted to admit atmospheric air into the interior of the submarine; and

(2) an operator-controllable control valve, positioned within said conduit member, for controlling the intake of atmospheric air into said conduit, said control valve being alternately shiftable at operator selection between an air-precluding position and an air-admitting position in said conduit member;

3,139,054 5 6 (b) liquid transport means, associated with said snorkel, pletely envelops the Weater-side of said air-intake for transporting hot brine from a source of hot brine control valve.

Within said submarine to the area of said air-intake References Cited in 1he file of this patent control valve; and

(0) means, in fluid communication with said liquid 5 UNITED STATES PATENTS transport means and mounted on said snorkel in a ,361 Bowers Nov. 6, 1917 position near said control valve and on the Weather 2,901,164 w May 1 1935 side of said control valve, for controllably issuing as 2,693,175 Hlckok 1954 spray the hot brine, transported by said liquid trans- FO PATENTS port means, over said air-intake control valve in the 10 2,100 Great Britain May 30, 1877 form of an umbrella-like configuration which com- 26,486 Great Britain Dec. 14 1893 

1. A METHOD FOR PREVENTING ICING OF A SUBMARINE SNORKEL HAVING AN AIR INTAKE CONTROL VALVE IN THE HEAD PORTION THEREOF WHICH COMPRISES PICKING UP HEATED WATER FROM ANY SOURCE OF HEATED WATER ABOARD SAID SUBMARINE, CONVEYING SAID HEATED WATER TO THE AREA OF SAID AIR INTAKE CONTROL VALVE AND FORMING BY NOZZLE DISCHARGE OF SAID HEATED WATER AT THE WEATHER SIDE OF SAID AIR INTAKE CONTROL VALVE AN UMBRELLA-LIKE SPRAY CONFIGURATION WHICH COMPLETELY ENVELOPS THE WEATHER-SIDE OF SAID AIR INTAKE CONTROL VALVE. 